Monday, February 06, 2012

Audi’s safety systems do the thinking

Audi is developing a sensor system that will allow its cars to park themselves in a garage with just the push of a button.

Active safety is playing an increasingly more important role in the modern automobile. Electronic stability control (ESC) systems became standard fitment on all 2012 light-duty vehicles. The reason is not difficult to grasp when you look at the numbers.

According to the U.S. National Highway Traffic Safety Administration (NHTSA), a vehicle equipped with ESC is 35% less likely to be involved in a crash. The U.S. Insurance Institute for Highway Safety (IIHS) goes further, suggesting that it cuts fatal crashes by 43% and the likelihood of a fatality due to a rollover by a whopping 77% to 80%! The next phase of active safety has to do with predicting an incident and then taking corrective action before it occurs.

Audi has a number of systems, each of which is designed to reduce the risk of injury caused by a crash. The umbrella under which many of these systems reside is called Audi pre sense. It does exactly what its name implies — it looks for a potential incident and begins to take corrective action before the big bang occurs. The basic system uses the electronic stability control system. When the car begins to deviate from the driver’s intended line, the system turns on the hazard warning lights, closes the windows and sunroof (if open) and snugs up the seat belts, which pulls the riders back into their seats and readies them for the potential impact.

Farther up the chain is pre sense front. This system uses the active cruise control and its ability to control the speed of the vehicle. Before taking charge, the system first attempts to draw the driver’s attention to the potential incident by giving visual and audible warnings. If the driver does nothing, it attempts to spur them to action by dabbing the brakes momentarily. If the driver still does nothing to avoid what is now a looming problem, the system applies up to 30% brake pressure to slow the vehicle, which reduces the severity of the impact.

The top version, pre sense plus, goes one further by applying full brake pressure 0.5 seconds before the impact. In the real world, this action can take as much as 40 kilometres an hour off the impact speed, which dramatically reduces the severity of injury. Future pre sense generations will also look at the potential severity of the impact and tailor the seat belt pretensioners and air bag deployment to the type of impact.

Beyond that, Audi is expanding its active safety portfolio by adding adaptive cruise control with stop and go. It uses a pair of radars that monitors the road ahead for 250 metres. It then controls the speed of the vehicle and the distance by which it tails the car ahead. The system works over the entire speed range (zero to 250 km/h) and it can bring the vehicle to a halt if that’s what the car ahead does. It is a truly freaky feeling letting a system prevent you from running into the back of a car.

The next evolution will add a laser scanner (it can be likened to a very sophisticated bar code scanner). This debut is pre sense city. It allows the vehicle to track the car ahead and mimic what it does by not only controlling the gas and brakes but also by using the active steering system (part of Audi’s self-park system) to track the car ahead. Mercifully, it is smart enough not to follow the car if it does a hard right out of the lane.

Audi’s lane departure warning system is also a little different. As well as vibrating the steering wheel when the driver begins to drift out of the lane, it, too, uses the active steering and a camera that monitors the lines to put the car back in the centre of the lane. It really does encourage the use of the turn signal — this cancels the action.

Another future technology is a self-parking feature, and it goes well beyond anything offered today. Using a variety of sensors, the car actually parks itself without the driver being in the vehicle. Pull up outside the garage, open the door, get out and push a button on the key fob. The system then selects Drive and inches into the garage all by itself. When it senses the wall at the end of the garage, it stops, selects Park, shuts the engine down and applies the parking brake. It also closes any open window and locks the doors. The next morning, the driver simply pushes the same button and it backs out to a predetermined spot on the driveway. If at any time it detects an obstacle, it will stop and wait for the problem to clear. So, if little Johnny leaves his toy dump truck in the middle of the garage, it will not get bulldozed!

The other demonstration of note was a system designed to ease the chore of backing an Audi up with a trailer in tow. The secret to the ability lies in a special tow hitch ball that measures the angle of the trailer relative to the car. It is very simple to use. When backing up, the driver uses the Multi-Media Interface’s central controller to guide the car, not the steering wheel. The system uses the active steering to dial in the inputs needed to put the trailer where the driver wants with uncanny precision. It turned a complete trailer-towing neophyte (me) into a trailer tow pro in less time than it took to read this description. All I did was control the speed of the car. What will they think of next!